需要购买设计请加我们的QQ962120665，电话18730072785 |
摘 要
在电力系统运行过程中，时常会发生故障，且大多是短路故障。短路通常分为三相短路、单相接地短路、两相短路和两相接地短路。其中三相短路为对称短路，后三者为不对称短路。电力运行经验指出单相接地短路占大多数，因此分析与计算不对称短路具有非常重要意义。
分析计算不对称短路方法很多，目前实际最常用的方法是对称分量法。而以对称分量法为核心的计算方法又可有解析法和计算机程序算法等，本论文的主要工作即介绍这两种计算方法。解析法，是将微分方程代数化、暂态分析稳态化、不对称转化为对称并叠加完成不对称故障的分析与计算。计算机程序算法是在形成三个序网的节点导纳矩阵后，对其应用高斯消去法求得故障端点等值阻抗，根据故障类型选用相应公式计算各序电流、电压，进而合成三相电流、电压。
最后本论文将对上述两种计算方法做出比较。
本设计只分析暂态过程中的基频分量。
关键字：单相接地短路，两相短路，两相接地短路，对称分量法，节点导纳矩阵
Abstract
In the electrical power system movement process, it often breaks down, and mostly it will be the short trouble. The short circuit usually divides into the three-phase fault, the single line-to-ground fault，the line-to-line fault and the double line-to-ground fault. And the three-phase fault is the symmetrical short circuit, the latter three are asymmetrical short-circuits. The electric power service experience points out that the single line-to-ground fault occupies the majority, therefore the analysis and the computation of the asymmetrical short-circuit have very important meaning.
The analysis and the computation method to asymmetrical short-circuits is many, at present the most commonly used method is the symmetrical component method. By symmetrical component method as the core method of calculation, it can be divided into the analytical method and the computer program algorithm, etc, the paper primly introduces these two computational methods. The analytical method is to make the differential be equation algebra, make the transition condition analysis be stable state, is to make asymmetrical transforms and complete the analysis and the computation of the asymmetric fault. Algorithm is a computer program to form the three-node network admittance matrix and to achieve the endpoint equivalent impedance by the application of Gaussian elimination of its fault, after that it calculate various forewords current and voltage, then synthesis three-phase current and voltage according to the breakdown type.
Finally the paper will make the comparison between the two methods.
This design only analyzes in the transition process based on frequency component.
Key word：Single line-to-ground fault，Line-to-line fault，Double line-to-ground fault, Symmetrical component method, Node admittance matrix